Internets are widely used. For short-distance transmission, the information is transmitted by coaxial cables. The transmission limitation for the coaxial cables is about 500 meters. On the other hand, for long-distance transmission, to ensure the safety and stability of the information, optical fibers are applied for the transmission.
Fiber-optic communication becomes a popular wireless communication means in which information to be transmitted is inputted in a transmitter at a transmitting end, and the information is superimposed or modulated to a carrier wave which is served as an information carrier, then the modulated carrier wave passes the transmission medium and transmitted to a receiving end at remote where a receiver is applied to demodulated the original information.
A conventional drawer-type receiving box includes an optical fiber cassette and an optical fiber adapter for inserting optical fiber plugs. The cassette is a drawer slibably movable relative to the rail structures at two sides of the space in the box. Hence, the cassette can be slid out for wire organization, repair and maintenance, and management. However, in the conventional, the rail structure is fixed by locking with screws. As a result, the rail structure cannot be detached from the box rapidly. Consequently, the distance between the two rail structures can be applied to an optical fiber cassette with a single width. Therefore, how to solve the aforementioned problem is an issue.